1. Field of the Invention
The present invention relates to shuttle scanning systems, generally, and, more particularly, to pre-scanning for a shuttle-scanning process and apparatus in order to preclude a scan creation of a gap by scanning a document with a carrier sheet or by scanning only the document during recirculation of the document.
2. Discussion of Related Art
In recent years, several office automation machines have been combined into one system. Remarkable progress has been made toward the development of a multi-tasking system by combining a printer, a facsimile machine, a scanner, together with other components of image formation equipment. Exemplary practice in the art is found in the structure illustrated by the Image Reproducing Apparatus With CCD Scanner And Bubble Jet Printer Simultaneously Driven By A Common Belt In Opposite Directions And Operated Asynchronously of Charles D. Wilson, U.S. Pat. No. 4,839,741, and the Scanner Document Absence Code System of J. R. graves and J. E. Summers, U.S. Pat. No. 5,119,213, with the concept of making an initial "rough reading" by the Image Reading Apparatus of Teruhiko Uno, U.S. Pat. No. 5,128,777; while multi-tasking is illustrated in the Combined Electrographic Printer, Copier, And Telefax Machine With Duplex Capability of Kensuke Fukae and Shozo Kaieda, U.S. Pat. No. 4,814,798. More recent efforts in the art are found in the High Efficiency Multi-image Scan Method of Michael Hsieh, et al, U.S. Pat. No. 5,719,386 and the Add-on Scanner For Existing Ink Jet Printer of C. K. Lim, et al, U.S. Pat. No. 5,532,825. I have noticed that the art fails to adequately address the occurrence a scan gap when the document to be subjected to a normal scan is fed backwardly after completion of pre-scanning; consequently, a section of the document called a scan gap, is not available to be scanned.